Some animals -- like the octopus and cuttlefish -- transform their shape based on environment, fending off attackers or threats in the wild. For decades, researchers have worked toward mimicking similar biological responses in non-living organisms, as it would have significant implications in the medical arena. Now, researchers at the University of Pittsburgh have demonstrated such a biomimetic response using hydrogels -- a material that constitutes most contact lenses and microfluidic or fluid-controlled technologies.